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CVE-2026-43024 Linux CVE debrief

A vulnerability has been identified in the Linux kernel, specifically in the netfilter component of nf_tables. This vulnerability involves the rejection of immediate NF_QUEUE verdicts. The nf_tables is a packet filtering framework that provides a more flexible and efficient way to filter packets than the traditional iptables. NF_QUEUE is a verdict that queues the packet for user-space processing. However, immediate NF_QUEUE verdicts are not used by userspace nft tools and can be problematic. To address this, the Linux kernel has introduced a fix to reject immediate NF_QUEUE verdicts globally, including for the arp family which does not provide queue support but could still be affected.

Vendor
Linux
Product
Unknown
CVSS
MEDIUM 5.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-01
Original CVE updated
2026-07-14
Advisory published
2026-05-01
Advisory updated
2026-07-14

Who should care

System administrators and users of Linux operating systems should be aware of this vulnerability, especially those who manage or use systems that could be affected by the exploitation of this issue. This includes but is not limited to servers, workstations, and IoT devices running vulnerable versions of the Linux kernel.

Technical summary

The vulnerability CVE-2026-43024 is related to the netfilter component of the Linux kernel, specifically within nf_tables. The issue revolves around the handling of immediate NF_QUEUE verdicts, which are not typically used by userspace nft tools. The Linux kernel has implemented a fix to globally reject such immediate verdicts to mitigate potential security risks. This change affects various versions of the Linux kernel, including but not limited to versions 4.19.307, 5.4.269, 5.10.210, 5.15.149, 6.1.76, 6.6.15, 6.7.3, and 6.8.1. Users and administrators should ensure their systems are updated with the latest kernel patches to prevent exploitation.

Defensive priority

Medium

Recommended defensive actions

  • Apply kernel updates to ensure systems are running with the latest security patches.
  • Review system configurations and ensure that nf_tables is properly configured.
  • Monitor system logs for any suspicious activity related to nf_tables and NF_QUEUE.
  • Consider implementing additional security measures such as firewall rules and intrusion detection systems.
  • Perform a thorough review of system configurations and network architecture to identify potential vulnerabilities.
  • Implement asset inventory management to track and manage Linux systems.
  • Establish a process for tracking and addressing exceptions during remediation.

Evidence notes

The CVE record was published on 2026-05-01T15:16:46.760Z and was last modified on 2026-07-14T13:18:51.963Z. The NVD entry is currently Modified. Multiple patches have been provided by the Linux kernel maintainers to address this vulnerability.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-05-01T15:16:46.760Z and has not been modified since then. The NVD entry is currently Modified.